Early change in lean tissue mass after peritoneal dialysis: prevalence, risk factors, and clinical implications.

Background: Muscle wasting has been linked to negative clinical outcomes in patients undergoing peritoneal dialysis (PD). However, it remains unclear how early changes in muscle mass after the initiation of PD affects the clinical outcome. This study aimed to identify factors influencing changes in lean tissue mass (LTM) over six months in new PD patients and to assess their prognostic significance.

Methods: We conducted a study of 90 new PD patients. Over a six-month period, we recorded changes in LTM and adipose tissue mass (ATM) using bioimpedance spectrometry. Outcome measures included patient and technique survival rates.

Results: After 6 months of PD, body weight and body mass index remained unchanged, but 42 patients (46.7%) had decrease in LTM for ≥ 1 kg. The percentage of LTM (LTMp) also dropped from 63.4 ± 13.6% to 61.5 ± 13.4% (p = 0.006), accompanied by an increase in ATM. Multiple linear regression models showed a strong correlation between changes in LTM and ATM; for every 1 kg increase in ATM, there was a 1.01 kg decrease in LTM (95% confidence interval: 0.797 to 0.855, p < 0.0001). However, the change in LTM during the first six months of PD was not associated with patient or technique survival rates.

Conclusion: Although the overall body weight was static, there was a trend of reduction in LTM and a concommitant increase in ATM during the first 6 months of PD. However, these changes were not associated with adverse clinical outcome.